From nobody Sun Feb 8 23:04:12 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 03FA6C7EE23 for ; Mon, 29 May 2023 06:14:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230521AbjE2GOm (ORCPT ); Mon, 29 May 2023 02:14:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43158 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230342AbjE2GOd (ORCPT ); Mon, 29 May 2023 02:14:33 -0400 Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 70F8EF1 for ; Sun, 28 May 2023 23:14:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1685340869; x=1716876869; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=BU9rFfysv4elNLJ2GHzqi2liUatC3EzDYJWAUuFdw+0=; b=cJxrFtlCwIuI2Qjv4t0svwIYrYf8UN4laXVC3qIsq+xZpAtNS+1bPG4V w2QJ0pcsaEAY83MpX20jynYcuQx85NV01amjXU4pw5N6Wce5yK3+ICZco 41D0VgIKfZ9U9tBkRoE7eoSFx7zxvflNl4lFRqZMY45WpwvyXiKECzKYT elWTHgSozyruFTewpFqcuPxnm6cR/8d9Em19AQ7PGiPVR9H9wt/F3wPRA 2g10+RcObIGDHtdXWDAVaetUpmjRsxIdChk2PtJOWHZ0/DvM+vgpYAjU6 bVaEpse+rgKHOv+FqDZRH/c4SEyvpOKupgPB0uKd3jBU92DGtOy9Zzq3I A==; X-IronPort-AV: E=McAfee;i="6600,9927,10724"; a="357881854" X-IronPort-AV: E=Sophos;i="6.00,200,1681196400"; d="scan'208";a="357881854" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 May 2023 23:14:28 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10724"; a="1036080010" X-IronPort-AV: E=Sophos;i="6.00,200,1681196400"; d="scan'208";a="1036080010" Received: from azhao3-mobl1.ccr.corp.intel.com (HELO yhuang6-mobl2.ccr.corp.intel.com) ([10.255.28.126]) by fmsmga005-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 May 2023 23:14:25 -0700 From: Huang Ying To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Huang Ying , Yosry Ahmed , David Hildenbrand , Hugh Dickins , Johannes Weiner , Matthew Wilcox , Michal Hocko , Minchan Kim , Tim Chen , Yang Shi , Yu Zhao , Chris Li Subject: [PATCH -V3 4/5] swap: remove get/put_swap_device() in __swap_duplicate() Date: Mon, 29 May 2023 14:13:54 +0800 Message-Id: <20230529061355.125791-5-ying.huang@intel.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230529061355.125791-1-ying.huang@intel.com> References: <20230529061355.125791-1-ying.huang@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" __swap_duplicate() is called by - swap_shmem_alloc(): the folio in swap cache is locked. - copy_nonpresent_pte() -> swap_duplicate() and try_to_unmap_one() -> swap_duplicate(): the page table lock is held. - __read_swap_cache_async() -> swapcache_prepare(): enclosed with get/put_swap_device() in __read_swap_cache_async() already. So, it's safe to remove get/put_swap_device() in __swap_duplicate(). Signed-off-by: "Huang, Ying" Reviewed-by: Yosry Ahmed Cc: David Hildenbrand Cc: Hugh Dickins Cc: Johannes Weiner Cc: Matthew Wilcox Cc: Michal Hocko Cc: Minchan Kim Cc: Tim Chen Cc: Yang Shi Cc: Yu Zhao Cc: Chris Li Reviewed-by: Chris Li (Google) Reviewed-by: David Hildenbrand --- mm/swapfile.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/mm/swapfile.c b/mm/swapfile.c index e9cce775fb25..4dbaea64635d 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -3264,9 +3264,7 @@ static int __swap_duplicate(swp_entry_t entry, unsign= ed char usage) unsigned char has_cache; int err; =20 - p =3D get_swap_device(entry); - if (!p) - return -EINVAL; + p =3D swp_swap_info(entry); =20 offset =3D swp_offset(entry); ci =3D lock_cluster_or_swap_info(p, offset); @@ -3313,7 +3311,6 @@ static int __swap_duplicate(swp_entry_t entry, unsign= ed char usage) =20 unlock_out: unlock_cluster_or_swap_info(p, ci); - put_swap_device(p); return err; } =20 --=20 2.39.2